All posts tagged ‘cryptography’

The Central Intelligence Agency recently declassified the six oldest documents still considered classified by the US government. This was not the sort of big reveal that some people apparently expected. In fact, many of the secrets held by the last classified documents from the First World War have for decades been widely used in elementary school science projects: Homemade invisible inks. While it’s a little embarrassing that the CIA was still treating the contents of grade school classrooms like legitimate national security concerns, it’s also a perfect occasion for Geek Moms to engage our kids in some Super Spy shenanigans.

I was a young cipher-junkie, so I already have a few hidden writing techniques up my sleeves. However, not everyone grew up with my odd hobby. Because of that, and because my son is also new to secret messaging, I decided to video his induction into the amateur spy club and share it here.

In the video below, you’ll find some easy invisible inks to make at home, as well as a few other ways to hide your subversive messages and love notes in plain sight. But this is just an introduction – an invitation, if you will – to look at the world obliquely and to explore the subtle side of chemistry, physics, logic and even history.

There were several methods of secret writing that I didn’t have time to include in this video, including UV inks, cryptography, and my personal favorite: Steganography. But I did take a moment to hide a brief message in the first line of this post…